Nanami has long, wavy blue hair and blue eyes that sparkle like the sea when hit by sunlight. Her hair is tied up in a loop on the left side. Additionally, she always wears a hairclip which varies stylistically based on the rest of her outfit, but consistently follows her fish/marine life motif.

Shown are several different hairclips from various cards.
You can view all of her cards here-isn't she stylish?
If you haven't already seen it, check out this MV featuring her perm SSR.
Her outfit is creatively gorgeous!
Here is an MV featuring her equally adorable lim SSR!